Adrian G. Dan

Age and gender exert differential effects on blood lipids in patients after LAGB and LRYGB

BACKGROUND Although bariatric surgery is known to exert favorable effects on dyslipidemia, few studies have systematically considered how the demographic variables might modulate the outcomes. The aim of the present study was to examine the interactive effects of gender, age, and surgery type on dyslipidimia in bariatric surgery patients at a tertiary hospital in the United States. METHODS In a retrospective review of 294 patients who had undergone laparoscopic Roux-en-Y gastric bypass (LRYGB) or laparoscopic adjustable gastric bypass (LAGB), we examined the changes in lipid profiles and antihyperlipidemic use for ≤4 years postoperatively. The data were analyzed using longitudinal mixed modeling methods, in which the effects on lipid concentrations and medication use were tested in models with gender, surgery type, age, postoperative duration, and all possible interactions entered as factors. RESULTS Significant 2-way interactions of surgery type*time were found for total cholesterol and high-density lipoprotein cholesterol, gender*time for high-density lipoprotein cholesterol, and age*time for triglycerides. A 3-way interaction of surgery type*age*time was noted for low-density lipoprotein cholesterol. For older patients, low-density lipoprotein cholesterol was reduced by 20% from baseline in the LRYGB group but did not lessen significantly in the LAGB group. In the younger patients, however, decreases from the preoperative concentrations were not evident in either surgery group. An interaction of surgery type*time on antihyperlipdemic medication use, in which values changed significantly from baseline was found in both groups. However, the pattern in the LRYGB patients opposed that in the LAGB patients. CONCLUSION Our results have demonstrated that bariatric surgery imparts a pronounced improvement in the blood lipid profile of recipients; however, these effects might be moderated by other factors, such as age and gender, independently of the baseline weight status of the patients.

The Effect of Marital Status on Weight Loss After Bariatric Surgery is Moderated by Depression

Background: Presence of depression and /or a lack of appropriate social support may exert deleterious effects on postoperative weight loss in bariatric surgery patients. The purpose of this study was to investigate the interactive effects of surgical procedure and marital status on weight loss in these patients, and to assess the impact of depression on these effects. Methods: A retrospective review was performed of patients who underwent laparoscopic gastric bypass or banding surgery (LRYGB or LAGB) at a single institution from 2005-2007. Our sample included 62 patients who had values for all time points for percent excess weight loss (%EWL) preoperatively, and 1, 3, 6, 12, and 18 months postoperatively. Data were analyzed using SAS 9.1, where %EWL was tested in mixed models for effects of marital status, surgical procedure, time, and all interactions of the three. Correlation analyses were used to examine the relationship between baseline depression and %EWL within categories of marital status. Results: Interactions were found between surgery-type and time, and marital status and time. LRYGB patients had greater %EWL compared to LAGB at all postoperative time points, and %EWL for Married patients was less than that of Singles at 12 and 18 months. There was a marked, inverse relationship between depression and %EWL for the Single group, but not the others. Conclusions: Interactions between these variables suggests that the effects of marital status on %EWL may be modulated by depression. Further studies are needed in order to examine these relationships in samples including more even distributions of sex and marital status.

Two-trocar cholecystectomy by strategic laparoscopy for improved cosmesis (SLIC).

Results of this study suggest that strategic laparoscopy for improved cosmesis cholecystectomy is feasible, safe, and decreases the cumulative incision length as well as the number of incisions in patients with favorable body habitus and previous surgical history.

A pilot study on the biomechanical assessment of obstructive sleep apnea pre and post bariatric surgery

Obesity is a major risk factor for obstructive sleep apnea patients. In obese patients the severity of this risk can be reduced by bariatric surgery. This pilot study investigates the perioperative effects of bariatric surgery on obstructive sleep apnea and on the physical and biomechanical characteristics of the upper airway. Polysomnography and computer tomography data for 10 morbid obese patients promoted for bariatric surgery were conducted before surgery and at 6 and 12 months postoperatively for assessment of the oropharyngeal anatomy, and subsequent three-dimensional modelling of the airway. Mean values for the apnea/hypopnea index and body mass index significantly reduced after surgery. To combine the effect of changes in the upper airway volume and body mass index, a new volume body mass index is introduced. This index increases with a successful bariatric surgery. Although bariatric surgery leads to an effective weight reduction for all age groups, for obstructive sleep apnea patients it may be effective for middle age, less effective for 50-60 years, and further less effective for patients over the age of 60 years.

Obesity-The Epidemic Crisis of Our Time.

Seldom does a specific disease entity become a “plague” to humanity and thereby define that period of time in the history of mankind. Today, one such phenomenon is the obesity epidemic, which spares no socioeconomic subset or geographic region of the world. The problem has reached a critical point becoming profoundly ubiquitous in the general population. A drastic change has occurred in the past few decades, unlike any other seen in the evolution of the human species. Rates of morbid obesity are skyrocketing to unprecedented levels, particularly in more affluent regions of the world. The simultaneous advances in agriculture, industry, and technology are testing our species in novel ways. In fact, more individuals now suffer from obesity and its health ravages than endure hunger and malnutrition. For the first time in the Surgical Clinics of North America series, Metabolic Surgery has taken precedence in the title of an issue, emphasizing the metabolic capabilities of surgical procedures that have been refined over the span of six decades. These operations have been developed into some of the most effective and well-studied therapies in modern medicine. The myth that “weight loss is the sole objective of bariatric surgery” has dissipated and given way to the avalanche of scientific evidence validating the metabolic benefits made possible with surgical alterations of the gastrointestinal tract. Every single organ system is impacted by morbid obesity and may be positively affected by the metabolic changes conferred with bariatric procedures. The potential to prevent and resolve associated conditions, significantly reduce the incidence of malignancies, and increase longevity makes bariatric surgery the ultimate weapon in the era of population health management. Obesity reaches far beyond the issues limited to the patient-physician relationship, and the psychologic, social, cultural, and economic ramifications penetrate all facets of our life. This issue is designed to cover a wide range of such topics pertinent to contemporary bariatric practice. It is intended to serve as a current and robust reference for surgical residents, bariatric fellows, practicing surgeons, collaborating physicians, and health care policymakers.

11 Postoperative Pathways in Minimally Invasive Bariatric Surgery

Obesity has become one of the greatest public health threats of our time, impacting a significant segment of the world’s population. This epidemic has increased the demand for therapies to achieve weight loss and resolve associated comorbidities. Surgery has been proven to be the most effective modality. The number of surgical procedures performed annually in the United States and worldwide continues to rise. Along with improving and refining bariatric procedures, clinicians have endeavored to improve perioperative care. Evidence-based postoperative care pathways have been standardized to decrease postoperative complications, improve resource utilization, and lower costs.

4 History of Bariatric and Metabolic Surgery

Bariatric and metabolic surgery has blossomed over the last 60 years from its experimental origin to become one of the most astounding weapons in the arsenal of modern medicine. The evolution has taken place in a stepwise fashion through the inventive efforts of surgeons who were farsighted enough to envision the potential utility of altering gastrointestinal anatomy to change physiology. A multitude of procedures have come and gone, but with the dedication of pioneers studying the effectiveness, drawbacks, and safety, our knowledge of the field has grown immensely. This has led to the sound and unrivaled surgical treatments for obesity that we can offer today.

Fluid Dynamic Analysis of Upper Airway of an Obstructive Sleep Apnea Patient Pre and Post Surgery

The present study compares flow parameters (pressure drop, velocity, and shear stress) in the upper airway between pre- and post-bariatric surgery obstructive sleep apnea (OSA) patients. CT images of the upper airway were obtained prior to and six months post bariatric surgery in patients with a comorbid OSA. In-house software was used to reconstruct 3D geometric models of the upper airway, and fluid flow simulations were conducted using commercial computational fluid dynamics (CFD) software. Results show that pressure drop in the upper airway and velocity at the throat decrease post-surgery. Shear stress on the airway walls also decreased markedly. These trends were expected, however more patients must be analyzed and correlations must be drawn between these fluid dynamic parameters and the pathophysiology of the upper airway in OSA.© 2012 ASME